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Turning into a zombie meant getting his turn in the "more bloody and gross" makeup trailer

There was a bullet involved in the original plan for the scene, but it was changed to a stabbing

Milton might be dead on "The Walking Dead," but actor Dallas Roberts (who portrayed the Governor's one-time lackey) is very glad to be alive -- and finally able to talk about the show's season three finale. "You can't imagine the pressure that's finally off," he said. "I'm finally able to have all the cards on the table."

Before Sunday night, Roberts had only told three (OK, maybe four) people about how Milton would become a walker, keeping the list limited to his girlfriend, his kids, and maybe a trusted friend who lived near where they shot the show in Atlanta. "I may have taken an authorized photo of myself as a walker, and I may have sent that to him under threat of dismemberment if he passed that along," Roberts said. "But the last thing you want to do is spoil season three of 'The Walking Dead' where you turn into a zombie and kill Andrea!"

Turning into a zombie meant Roberts finally got his turn in the chair in the "more bloody and gross" makeup trailer reserved for walkers. All season long, Milton has been kept squeaky clean, raising serious questions such as, "Where is he sending his dry cleaning?" Roberts laughed. "How is he showering three times a day? Where is he getting all his razors?"

"From the beginning, they were like, 'No sexy dirt on him. He's always clean. He's always tucked in,'" Roberts continued. "I was like, 'Wow, there's something about this that's going to go somewhere.' And nope! He's just the clean guy. No sexy dirt for me. Milton never got the sexy anything, did he?"

But for the few scenes in the finale, Roberts was sexy, dirty, bloody, the whole shebang, as Milton was left in a locked room to turn and "tear the flesh from (Andrea's) bones," whether he liked it or not. That scene meant he got to go through a lot of emotional turmoil, "knowing she's going to be taken out, knowing it's over, and everything he worked for is going to die, and someone he cared for is going to die."

Milton didn't imagine that he would be "used as a tool to take Andrea out" as well, and if he had, "he would have behaved differently," Roberts said. "I think he thought there would be a bullet in his head, and that's it."

In the original plan for the scene, there actually was a bullet involved, but during the reshoot, it was changed to a stabbing. Either way, Milton had to collapse, he said, "in a pool of fake viscous blood that sort of cooled and crackled for hours and hours and hours." To make shooting that part of the finale a little easier, his co-star David Morrissey kept him in stitches beforehand with some "gallows humor."

"Before the door opened and he throws me to my knees, he and I were crying, laughing, at the jokes we were making," Roberts said. "I can promise you that they were completely inappropriate, and that they were hilarious. After a while, it wasn't even that it was funny as much as that we needed to straighten up before that door opened. It was like laughing in church, or laughing in school."

But no matter how much fun he had on set, don't expect Milton to be back in the form of flashbacks or visions a la Lori for Rick.

"I don't think anyone wants the Governor to see Milton in a white dress on a balcony!" Roberts laughed. (Plus Roberts just landed a regular gig on "Unforgettable" and remains a recurring guest star on "The Good Wife.")

Besides, assuming he was on the outs, Roberts swiped a beaker that Milton used to use. "I wasn't going to take the clothes, for sure," he said. "I mean, they were great clothes for Milton, but not for Dallas. Pleated khakis!"